This invention relates generally to oral hygienic care, and more specifically to methods and apparatus utilizing acoustically oscillated abrasives entrained in a low pressure water stream for removal of foreign material from the teeth and treatment of gingival tissues in the prevention of periodontal disease.
Periodontal disease is widespread throughout the world, and is the major cause of tooth loss in persons 35 years and older. Periodontal disease can also lead to more serious consequences including degeneration of alveolar bone structure, and serious infection. The incidence of dental caries and associated periodontal disease is a function of the presence of food particles and other oral debris and dental plaque in close contact with and between the teeth over a period of time. The most effective means of combating the rising incidence of periodontal disease is through education of the public in the practice of proper dental prophylaxis, and the provision of effective instruments to aid them in removal of food debris and plaque necessary in maintaining good oral hygiene.
In the field of home dental prophylaxis, mechanical brushing with a dentifrice is the conventional and most widely used technique for daily removal of oral debris and plaque buildup. Brushing is augmented to some extent by flossing and more recently through use of a pulsed, high pressure water jet to facilitate removal of particles between teeth and in inaccessible reaches of the mouth. Mechanical brushing; however, is a time consuming process if properly done, and motivation to maintain a proper daily regimen, including brushing, flossing and water jet cleaning is difficult to instill. Furthermore, because of the irregular topography of the teeth, inaccessibility of some areas, manual dexterity required, and difficult gingival tooth interface area, these conventional techniques are not fully effective. Mechanical brushing does not clean between teeth, nor at the gingival interface; flossing will remove particles between teeth, but does not affect plaque; and water jet rinses away oral debris in inaccessible areas of the mouth, between teeth, and at the gum line, but does not remove plaque. The high pressure of the water jet, 60 to 90 psi, may also damage gums and lead to dangerous tooth gum separation. Due to the demands of the regimen and the limitations of the instruments and techniques, the brushing, flossing and water jet system does not provide the most efficacious results in oral hygiene.
Improvements to the basic cleaning system have been added from time to time. Power driven tooth brushes have reduced the need for manual dexterity and have improved brushing time and gum massage, however, they still do nothing about deposits of plaque and debris between teeth, and flossing is still necessary.
Acoustic cleaning, in particular ultrasonics, has been widely utilized in industrial cleaning applications for many years, and there have been numerous attempts to apply similar techniques to the cleaning of teeth with varying degrees of success. There have been three basic approaches to utilizing ultrasonic energy for dental care. The simplest is the ultrasonic toothbrush which consists essentially of a normal power driven toothbrush head oscillated at ultrasonic frequencies. This device improves cleaning, stain removal, and gum massage, but does not reach the areas between teeth. Another development is the ultrasonic scaler. In this device, electrical energy and water are fed to a handpiece. The handpiece contains a magnetostrictive element to convert the alternating electrical current into high frequency mechanical vibrations. These ultrasonic vibrations are coupled to a thin metal scaling tip resulting in a linear tip motion of from 0.08 to 0.3 mm at the frequency of typically 16,000 to 40,000 Hz. The water fed into the handpiece is used to cool the magnetostrictive element and is then directed in a stream onto the vibrating scaling tip. The water sprayed onto the tip is atomized by the rapid vibrations, and a caviatation action produced in the vicinity of the tip will remove plaque and calculus. Although this method of plaque removal is highly effective, the high energy generated by the oscillating scaling tip can be dangerous and use of ultrasonic scaling devices must be left to trained professional dental personnel. If tip pressure is excessive severe damage can result including denudation of alvelolar bone, damage to tooth buds, sequestrum of the maxilla, pathalogic fractures, and root surface damage. Contact of the scaling tip with gums can cause painful lacerations. The potential dangers of improper use make the ultrasonic scalers entirely inappropriate home prophylaxis.
The third method normally employed introduces ultrasonic energy directly into a stream of water. At high power levels, this ultrasonic energy produces cavitation within the waterstream itself. This stream can then be pulsed or steady streamed onto the teeth and the collapsing cavitation bubbles produce intense pressure shocks which break away plaque through a microfatiguing action. However, the high pressure generated by cavitation can lead to erosion of tooth surfaces, and there is some evidence that nerve damage may result.
There are also devices which operate on a similar basis as the water jet previously described. These instruments project a concentrated, high pressure, slurry consisting of abrasives suspended in water, impacts upon the teeth at high velocity and the kinetic energy of the high velocity abrasives impacting on the plaque effectively removes it. This system, like the water jet, requires a high pressure stream which can cause gingival damage and accelerate tooth-gum separation, and is best not used for regular home care.
The present invention utilizes acoustically oscillated abrasive particles in a low pressure waterstream to create a scrubbing action. The scrubbing action of the abrasive particles effectively removes plaque, calculus, and food particles from teeth surfaces between teeth, and in the gingival interproximal area. It also stimulates gums and flushes particles from inaccessible areas of the mouth. The invention provides complete home dental care and does not require augmentation by flossing, water jet, etc. It is simple and easy to use, requires little manual dexterity, and is entirely safe. Thus, in accordance with this invention, the desired results of all the oral hygenic devices and techniques of the prior art are achieved without the usual attending disadvantages, by a new and novel system that is superior to any other available for daily prophylactic dental care in the home.
It is therefore an object of this invention to provide an improved method and apparatus for daily oral hygiene utilizing acoustic energy.
A further object of this invention is to provide a technique and apparatus completely safe and easy to use by adults and children in the home on a regular basis.
Another object of the present invention is to provide improved cleaning of plaque, calculus, and particles from hard to reach interproximal and gumline areas in one operation.
Other objects and advantages of this invention will become readily apparent hereinafter in the specification and drawings.